221121403 has 2 divisors, whose sum is σ = 221121404. Its totient is φ = 221121402.

The previous prime is 221121391. The next prime is 221121413. The reversal of 221121403 is 304121122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 221121403 - 2²¹ = 219024251 is a prime.

It is not a weakly prime, because it can be changed into another prime (221121413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110560701 + 110560702.

It is an arithmetic number, because the mean of its divisors is an integer number (110560702).

Almost surely, 2^221121403 is an apocalyptic number.

221121403 is a deficient number, since it is larger than the sum of its proper divisors (1).

221121403 is an equidigital number, since it uses as much as digits as its factorization.

221121403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 221121403 is about 14870.1514114685. The cubic root of 221121403 is about 604.7050475844.

Adding to 221121403 its reverse (304121122), we get a palindrome (525242525).

The spelling of 221121403 in words is "two hundred twenty-one million, one hundred twenty-one thousand, four hundred three".